The present invention relates to battery terminals used in flashlights, portable radios, communication terminals, model cars and other devices and, more particularly, to cooperating sets of terminals for the battery or battery pack and the receiving device which are configured to permit insertion of the battery into the device without regard to the orientation of the positive and negative terminals.
The conventional terminals which are used to connect a battery or battery pack to the electrical circuit of a receiving device such as a flashlight, radio, walky-talky, model car, etc., have only a single permissible orientation in which the positive and negative contacts of the battery are properly oriented to correspond to the positive and negative contacts of the receiving device. As a consequence, if the battery contacts are oriented improperly, positive to negative, relative to the receiving device, the receiving device will be inoperative and, in fact, the electrical circuitry of the device may be damaged.
An example of such a prior art arrangement is shown schematically in FIG. 1. There, a conventional battery 11 such as a transistor battery is adapted for connection to the electrical contact circuitry 21 of the receiving device. Battery 11 has negative and positive terminals 12 and 13 which form snap-in connections to the corresponding negative and positive terminals 22 and 23 of the receiving device. Quite obviously, proper physical and electrical connection is possible only when the battery is oriented so that positive terminal 13 is aligned with terminal 23 and negative terminal 12 with corresponding terminal 22. If, for example, the battery 11 is improperly oriented so that sides 14 and 15 are reversed, the opposite polarity terminals are brought into contact, rendering the device inoperative and possibly damaging it.
Another terminal arrangement is shown in FIG. 2 in the form of a battery pack 16 containing several individual batteries (shown in phantom) which are interconnected in series to negative and positive external terminals 17 and 18. In this case, the terminals do not form a coupling connection with the corresponding terminals 27 and 28 of device of circuit 26. Instead, a spring 29 is attached to the battery compartment wall 30 of the device to bias the terminals into engagement. Again, as in FIG. 1, there is only one proper orientation for the terminals. Positioning the battery with the terminals 17 and 18 reversed from their proper orientation prevents the receiving device from operating and may damage it.
Still another battery terminal arrangement is shown in FIG. 3. Here, the battery 31 is a standard flashlight cell in which the positive terminal or post 32 is located at the top of the battery and the base 33 provides ground contact. Receiving circuit 41 includes a positive terminal 42 at one end of the battery compartment and a ground terminal 43 at the opposite end. This arrangement is similar to that of FIG. 2 in that a spring 44 is mounted to battery compartment wall 45 to secure the battery 31 within the compartment. This arrangement is similar to that of FIGS. 1 and 2 in that there is only one proper orientation for the positive and negative terminals. However, the arrangement differs from that shown in FIGS. 1 and 2 in that proper orientation is obtained by switching a battery end-for-end rather than from side-to-side. In addition, the battery of FIG. 1, for example, can be inserted into the receiving battery compartment in four different orientations, only one of which is correct, whereas only two total orientations and one incorrect orientation are possible for the arrangement of FIG. 3.
The potential for incorrect, possibly damaging misorientation is perhaps only a minor inconvenience where batteries are replaced infrequently and in adequate ambient light. However, this situation can become more than a minor annoyance where a number of devices are used and/or battery replacements are frequent and/or battery replacement is done in low ambient light where correct orientation is not easily determined.
In view of the above situation, it is an object of the present invention to provide a battery terminal or contact arrangement in which correct positive-to-positive and negative-to-negative connections are made independently of the orientation of the battery contacts and the contacts of the receiving device.
It is another object of the present invention to provide a battery terminal arrangement which uses interdigitated battery and receiving terminals which permit the terminals to be reversed end-for-end without altering the contact polarity. As a result, proper polarity contact is always made between the battery and the receiving device.
It is still another object of the present invention to provide a battery terminal arrangement which includes interdigitated battery and receiving terminals and in which the battery terminals are provided on both sides of the battery. As a result, the battery can be reversed end-to-end or side-to-side without altering the contact polarity. Contact between the battery and the receiving device is, thus, completely independent of the orientation of the battery.